Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 06 May 2020 07:16:11 -0700
User-Agent: K-9 Mail for Android
In-Reply-To: <20200506140352.37154-1-yanaijie@huawei.com>
References: <20200506140352.37154-1-yanaijie@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain;
 charset=utf-8
Content-Transfer-Encoding: quoted-printable
Subject: Re: [PATCH v2] bpf, i386: remove unneeded conversion to bool
To:     Jason Yan <yanaijie@huawei.com>, davem@davemloft.net,
        kuznet@ms2.inr.ac.ru, yoshfuji@linux-ipv6.org, udknight@gmail.com,
        tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org,
        ast@kernel.org, daniel@iogearbox.net, kafai@fb.com,
        songliubraving@fb.com, yhs@fb.com, andriin@fb.com,
        john.fastabend@gmail.com, kpsingh@chromium.org,
        lukenels@cs.washington.edu, xi.wang@gmail.com,
        netdev@vger.kernel.org, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org
From:   hpa@zytor.com
Message-ID: <D11F36F6-BF28-4DEB-8AED-4486477130F8@zytor.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On May 6, 2020 7:03:52 AM PDT, Jason Yan <yanaijie@huawei=2Ecom> wrote:
>The '=3D=3D' expression itself is bool, no need to convert it to bool
>again=2E
>This fixes the following coccicheck warning:
>
>arch/x86/net/bpf_jit_comp32=2Ec:1478:50-55: WARNING: conversion to bool
>not needed here
>arch/x86/net/bpf_jit_comp32=2Ec:1479:50-55: WARNING: conversion to bool
>not needed here
>
>Signed-off-by: Jason Yan <yanaijie@huawei=2Ecom>
>---
> v2: change the name 'x32' to 'i386'=2E
>
> arch/x86/net/bpf_jit_comp32=2Ec | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
>diff --git a/arch/x86/net/bpf_jit_comp32=2Ec
>b/arch/x86/net/bpf_jit_comp32=2Ec
>index 66cd150b7e54=2E=2E96fde03aa987 100644
>--- a/arch/x86/net/bpf_jit_comp32=2Ec
>+++ b/arch/x86/net/bpf_jit_comp32=2Ec
>@@ -1475,8 +1475,8 @@ static int do_jit(struct bpf_prog *bpf_prog, int
>*addrs, u8 *image,
> 	for (i =3D 0; i < insn_cnt; i++, insn++) {
> 		const s32 imm32 =3D insn->imm;
> 		const bool is64 =3D BPF_CLASS(insn->code) =3D=3D BPF_ALU64;
>-		const bool dstk =3D insn->dst_reg =3D=3D BPF_REG_AX ? false : true;
>-		const bool sstk =3D insn->src_reg =3D=3D BPF_REG_AX ? false : true;
>+		const bool dstk =3D insn->dst_reg !=3D BPF_REG_AX;
>+		const bool sstk =3D insn->src_reg !=3D BPF_REG_AX;
> 		const u8 code =3D insn->code;
> 		const u8 *dst =3D bpf2ia32[insn->dst_reg];
> 		const u8 *src =3D bpf2ia32[insn->src_reg];

"foo ? true : false" is also far better written !!foo when it isn't totall=
y redundant=2E
--=20
Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E